Er对汽车框架用铝合金组织与性能的影响

对比分析了不同退火温度下不含Er和含Er铝合金显微组织、显微硬度、拉伸力学性能和断口形貌的变化规律。结果表明,在相同退火温度下,含Er铝合金的显微硬度都要高于不含Er铝合金;相同的退火温度下,含Er铝合金的抗拉强度和屈服强度都要高于不含Er铝合金;含Er铝合金相对不含Er铝合金的再结晶温度有明显提高,这主要与合金中Er元素添加后形成了与基体保持共格或者半共格关系的纳米级Al_3Er或者Al_3(Zr,Er)粒子有关。     

NaYF4:Er3+和NaYF4:Yb3+/Er3+上转换荧光纳米晶的制备与表征

以EDTA为螯合剂,采用络合共沉淀法合成了NaYF4:Er3+和NaYF4:Yb3+/Er3+纳米晶.分别采用XRD、SEM、荧光分光光度计对合成的样品进行了结构、形貌和上转换荧光分析.XRD结果表明,制备的NaYF4:Er3+和NaYF4:Yb3+/Er3+均为纯立方相;SEM结果显示,制备的NaYF4:Er3+和NaYF4: Yb3+/Er3+晶粒粒径都在100nm左右,与NaYF4:Er3+相比,NaYF4:Yb3+/Er3+晶粒尺寸分布更均匀,分散性更好,符合作为荧光标记材料的要求;上转换荧光分析表明,在980nm激光器激发下,NaYF4:Yb3+/Er3+的发光强度比NaYF4:Er3+提高了1个数量级.     

氩等离子体处理增强TiO_2∶Er/p~+-Si异质结器件的电致发光

在我们以前的工作[1]中,报道了基于重掺硼硅片(p~+-Si)上掺Er的TiO_2(TiO_2∶Er)薄膜的TiO_2∶Er/p~+-Si异质结器件的电致发光。本文研究了TiO_2∶Er薄膜的氩(Ar)等离子体处理对TiO_2∶Er/p~+-Si异质结器件电致发光的影响。研究发现:Ar等离子体处理使TiO_2∶Er/p~+-Si异质结器件与Er3+离子相关的可见和近红外电致发光都得到了显著的增强,同时也增强了与TiO_2基体中氧空位相关的电致发光。这是由于Ar等离子体处理显著提高了TiO_2∶Er薄膜中的氧空位浓度,不但增强了与氧空位相关的电致发光,而且增强了以氧空位为敏化中心的从TiO_2基体向Er3+离子的能量传递,从而增强了Er3+离子的发光。     

Er~(3+)掺杂ZnWO_4的合成及光催化活性研究（英文）

通过水热法合成了不同浓度Er3+掺杂Zn WO4纳米棒,并通过XRD、TEM和DRS等对其进行了表征。通过在模拟太阳光照射下光降解Rh B的速度来检测Zn WO4样品的光催化活性,研究了Er3+掺杂浓度对Zn WO4催化活性的影响。实验结果表明,当Er3+掺杂浓度为2mol%时,其光催化性能最好,因为引进Er3+后,Er3+加快了电荷分离效率。     

回热材料Er3Ni的氢化反应及其产物分析

回热材料Er3Ni的吸氢反应及其产物热物性可能是影响脉管制冷机性能的因素之一.研究了Er3Ni在不同活化条件下的氢化反应特性,通过反应过程的比较和氢化产物的分析,阐明了氢化反应前对Er3Ni进行的活化处理方法对Er3Ni的氢化反应过程及其产物特征所带来的影响.结合Er3Ni吸氢p-c-T曲线的测定,提出了两条制取不同含氢量Er3NiHx的技术路线.     

多孔YVO_4:Er纳米片的制备和表征

以Y2O3、Er2O3,乙二醇(EG)和NH4VO3作为反应前体,使用液相共沉淀法在低温下制备了多孔状的绿色发光材料YVO4:Er纳米片.将YVO4:Er纳米片在300℃和600℃加热2h,通过傅里叶红外光谱(FTIR)、X-射线衍射(XRD)、透射电镜(TEM)和荧光光谱(PL)对合成的YVO4:Er纳米片进行了表征,研究了加热温度对最终样品的形貌及多孔尺寸的影响.结果表明:由于Er3+的绿光发射,YVO4:Er在560 nm处有最强的发射峰.     

离子注入制备掺Er富硅氧化硅材料光致发光

利用离子注入方法制备了掺Er富硅氧化硅材料,用XRD,TEM方法研究材料微观结构,并测量了样品的光致发光(PL),研究了发光强度随测量温度的变化。试验表明:在1173K以上退火,注入硅集聚,形成φ(2-4)nm的纳米晶硅(nc-Si),纳米晶硅外面包裹非晶硅(a-Si),注入的Er离子分布在非晶硅中。通过非晶硅与硅纳米晶相耦合,非晶硅吸收部分硅纳米晶对Er的激发能量,降低了Er的激发效率;在T>150K时,激发态Er与非晶硅间的能量背迁移降低了Er的发光效率。     

行业信息

开发新型大中空吹塑产品TR571M取得成功日前,由茂名石化化工分部全密度车间成功开发出新型大中空吹塑产品TR571M,TR571M产品属于超高分子量高密度聚乙烯产品,主要用于吹制200升以上的大桶。TR571M产品具有优异的刚性、耐蠕变、抗磨损和耐环境应     

Er含量对FeSiB合金结构演变的影响

Fe Si B非晶合金价格低廉、软磁性能优异,其研究和应用备受关注。为了提高Fe-Si-B的加工性、生产效率和非晶稳定性,研究者通常会引入第四种元素或进行前驱体退火处理。本研究尝试引入Er元素以改善Fe Si B的结构和非晶性能。采用铜模吸铸法制备了不同Er含量的Fe75-xB8Si17-Erx(x=0～0. 8)(原子分数,%)合金,采用X射线衍射(XRD)仪、透射电子显微镜(TEM)和振动样品磁强计(VSM)表征了掺Er的Fe Si B合金的物相组成、微观形貌及磁性能,分析了Er含量对Fe Si B合金结构演变的影响。结果表明,当Er的添加量从0%增至0. 4%时,Er元素主要改变合金中α-Fe晶粒数量及粒径;在Er含量为0. 5时合金形成非晶态;但当Er含量大于0. 6%时,合金向过共晶点移动,促进了Fe-B相和Fe-Si相的生成,使得合金的非晶能力下降。     

纳米硅微晶对于Er离子掺杂的SiO_2薄膜的光致发光和电致发光的不同影响

本文利用Er和硅离子共注入热氧化SiO2薄膜的方法制备出Er离子掺杂的含纳米硅微晶的SiO2发光薄膜,在此基础上制备出ITO/SiON/Si-rich SiO2:Er/Si MOS结构电致发光器件,比较研究了硅微晶密度的变化对于MOS结构的电致发光和光致发光特性的影响。随着纳米硅微晶的增多,Er离子在1.54μm处的红外光致发光显著增强,显示出纳米硅微晶对Er离子光致发光的敏化作用。相反,对于电致发光来说,增加纳米硅微晶数量的同时也增加了SiO2薄膜中的电子俘获陷阱,电子在纳米硅微晶之间的隧穿降低了过热电子的数量和平均能量,因而降低了碰撞激发Er离子产生的电致发光效率。     

Preparation and ASE Spectrum of a Single-Mode Erbium Doped Tellurite Glass Fiber with D-type Cladding Geometry

Based on the host of tellurite glasses, the glass formation, preform manufacture, and fiber fabrication are described. The characterization of amplified spontaneous emission (ASE) from this newly fabricated single-mode Er3+-doped tellurite fibers is also presented. When pumped at 980 nm, a very broad erbium ASE around 1.53 μm was observed. The variations of ASE with fiber length and pumping power are measured and discussed. The output of 2 mW from Er3+-doped tellurite fiber ASE source was obtained under the pump power of 660 mW.     

Photoluminescence properties of the Yb:Er co-doped Al2O3 thin film fabricated by microwave ECR plasma source enhanced RF magnetron sputtering

The Yb:Er co-doped Al₂O₃ thin film was deposited on oxidized silicon wafers by microwave ECR plasma source enhanced RF magnetron sputtering, and annealed from 800 °C to 1000 °C. The photoluminescence at 1.53 μm of thin film was obtained under room temperature. The mixture phase structure of γ and θ is observed by XRD, and the compositions of the thin film are investigated by EPMA. The maximum PL intensity was achieved with O₂:Ar at 1:1, annealing temperature at 900 °C, and experimental ratio of Yb:Er at 1:3.6. The energy transfer mechanism between Er and Yb ions is supported by theoretical analysis and experiment results.     

2μm波段激光晶体研究进展

综述了以Ho、Tm、Er为激活离子、以YAG、YAP及YLF为基质的2μm波段激光晶体的特点及应用背景,详细讨论了几种重要2μm波段激光晶体的能级结构、光谱特性及器件研究进展,指出了适合LD泵浦是今后2μm波段激光晶体的发展方向.     

Preparation and visible emission of Er-doped 12CaO x 7Al2O3 powder

Er(3+)-doped 12CaO x 7Al2O3 (C12A7:Er3+) powders were prepared using the sol-gel method. X-ray diffraction, micro-Raman spectra and absorption spectra showed that C12A7:Er3+ powder had been obtained. Sharp and intense Er(3+)-related emission from C12A7:Er3+ powder with different Er3+ concentrations in the visible region at room temperature was investigated by analyzing the local structure of Ca atoms in C12A7, and it revealed that cation sites with low symmetry of the host were beneficial to the photoluminescence of Er3+ ions. The emission lines were attributed to two types of Er3+ centers, isolated Er3+ ions and complex centers formed by aggregation of Er3+ ions. The PL intensity might be affected by free oxygen species relative to Er3+ ions formed by charge compensation. The inverse temperature dependent luminescence from the upper level of 2H11/2 state and that from the lower level of 4S3/2 state implied that the thermalization or thermal equilibrium of electrons between the two closely emission states occurred.     

Experimental investigation of selective localisation by decomposition of the time reversal operator and subspace-based technique

The approaches of the active time reversal (TR) selective localisation based on the decomposition of the time reversal operator (DORT) and the TR multiple signal classification (MUSIC) location are presented. The waveguide experiment describes in detail the procedure of active TR location and shows that (i) the extended target could have multiple distinguishable eigenstates, unlike point-like targets in which one target corresponds to one eigenstate; (ii) the selective location can be achieved by means of the standard TR location in the presence of the suspended and bottom objects; (iii) compared with the standard TR location, TR MUSIC location based on signal subspaces performs better in locating non-resolved targets and has lower sidelobe levels to locate the extended target. Finally, the approach of acquiring the TR operator via array probing by weighting Hadamard?Walsh functions (to produce orthogonal beams) is discussed. The experimental result shows that the ambiguity surfaces of the standard TR location and the TR MUSIC location are greatly improved with this approach.     

Emission Properties of Yb3+/Er3+ Doped TeO2-WO3-ZnO Glasses for Broadband Optical Amplifiers

The YbS /Er3 doped TeO2-WO3-ZnO glasses were prepared. The absorption spectra, emission spectra and fluorescence lifetime of Era at 1.5μm, excited by 970 nm were measured. The influence of Er2Oa, Yb2Oa and Ohcontents on emission properties of Era at 1.5 μm was investigated. The optimum doping concentrations for Era and Yba is around 3.34× 1020 ions/cma and 6.63×1020 ions/cma, respectively. The peak emission cross section is 0.83～0.87 pm2. With the increasing concentration of Yba , the FWHM of Era emission at 1.5 μm in the glass increases from 77 nm to 83 nm. The results show that Yba /Era doped meO2-Woa-ZnO glasses are promising candidate for Era -doped broadband optical amplifier.     

宽带铋基掺铒光纤放大器增益及噪声特性研究

利用Er3 离子四能级结构速率方程组和光功率传输方程组,数值模拟了铋基掺铒光纤放大器(EDFA)的增益及噪声特性,模拟结果与实验报道结果取得了很好的一致。同时,详尽地分析了增益及噪声特性与光纤长度、泵浦功率和输入信号功率的关系,优化了放大器的性能,从理论上得出一个20dB增益带宽达76nm、噪声系数接近4dB的铋基EDFA。研究表明了铋基掺铒光纤放大器适合用作于现代DWDM系统中C L波段的光纤放大器。     

Enhanced pumping energy transfer between Si nanocrystals and Erbium ions in Si-rich SiOx sputtered using Si/Er2O3 encapsulated SiO substrate

We investigate the enhanced pumping energy transfer for near-infrared photoluminescence in high-density Si nanocrystals (nc-Si) and Erbium ions co-doped SiOx film, which is obtained by RF magnetron assistant sputtering the SiO target with partially encapsulated Si and Er2O3 chips. In contrast to conventional approaches, the use of SiO instead of SiO2 or Si substrate facilitates the formation of nc-Si in the sputtered SiOx, while the Er2O3 replaces the Er pellets to improves the Er3+ concentrations and prevent the precipitation of Er atoms in the nc-Si and Er3+ co-doped SiOx film. Er3+ ion concentration up to 0.325 atomic % is obtained in the SiOx:Er3+ film under a sputtering power of 100 Watts. Correlation between annealing parameters and energy transferring from nc-Si to Er3+ ions is demonstrated, which reveals an optimized annealing condition at 1000 degrees C for 240 min and highest energy transfer efficiency from 760 to 1535 nm by the nc-Si with size and density of 4.5 nm and 10(18) cm(-3) is observed.     

Adaptive trochoidal toolpath for complex pockets machining

This work proposes a novel adaptive trochoidal (TR) toolpath model for complex pocket machining. The proposed model is able to adjust its TR radius, while simultaneously offers an adaptive trochoidal step for generation of each toolpath cycle. With the varying radius, complex regions can be machined by a single strip of TR toolpath. Moreover, the step of each TR cycle can be adjusted with reference to the varied radius so as to maintain a constant radial depth of cut, and hence more stable material removal rate among all TR cycles can be achieved. For the pocket machining cases with complex inner and outer boundaries, experimental study has shown that the proposed TR toolpath can effectively minimise the fluctuation of cutting forces, and achieve better toolpath efficiency.     

Photophysics of resonantly and non-resonantly excited erbium doped Ge nanowires

We have fabricated Er doped germanium nanowires of different diameters by pulsed laser deposition and chemical methods. Er induced photoluminescence emission due to the intra-4f (4)I(13/2)→(4)I(15/2) transition of Er energy levels at 1.53 μm has been achieved at room temperature using both resonant (980 nm) and non-resonant (325 nm) excitation of Er ions. The observed 1.53 μm photoluminescence signal upon non-resonant 325 nm excitation is attributed to the Ge related oxygen deficiency centers surrounding the Ge core. For direct excitation, the infrared photoluminescence characteristics have been studied as a function of Er concentration, photon flux, and diameter of the nanowires. The Er related emission signal is found to be enhanced with increase in Er concentration, pump flux of 980 nm, and the nanowire diameter. The time resolved characteristics of the Er induced emission peak have been studied as a function of the pump flux as well as the diameter of the Ge nanowires.